#!/usr/bin/python

d_grand = raw_input("please input 0 - 100 grandes:")
try:
    f_grand = int(d_grand)
    if f_grand < 0 or f_grand >100:
        print("please input 0-100")
    elif f_grand >= 90 and f_grand <= 100:
        print("your grand is A",f_grand)
    elif 80 <= f_grand <= 89:
        print("B",f_grand)
    elif 70 <= f_grand <= 79:
        print("C",f_grand)
    elif 0 <= f_grand <= 69:
        print("D",f_grand)
    else:
        print("err")

except:
    print("err")
